One person is dead and four others injured after a knife attack in a supermarket in the German city of Hamburg.<br /><br />The motive for the attack is not yet known.<br /><br />A German newspaper showed a photo of the alleged attacker in the back of a police car.<br /><br />Passersby are reported to have tackled the suspect after he fled the scene and he suffered some injuries.<br /><br />Police say they believe the assailant acted alone.<br /><br />Germany has been on high alert for terrorist attacks for months. <br /><br />A knife attack in a Hamburg supermarket has left one person dead and seven injured, according to German media.<br /><br />Police say the suspect has been arrested and that it’s unclear what his or her motive was.<br />
